


Emerald Lazer's Undertale AU One-shot Collection

by Emerald_Lazers



Category: Undertale (Video Game)
Genre: Alternate Universe, Angst, Gen, HorrorTale, Other Additional Tags to Be Added, Post-Pacifist Route, core!Frisk
Language: English
Status: In-Progress
Published: 2016-05-01
Updated: 2016-05-01
Packaged: 2018-06-05 19:21:45
Rating: General Audiences
Warnings: No Archive Warnings Apply
Chapters: 3
Words: 4,377
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/6718489
Author URL: https://archiveofourown.org/users/Emerald_Lazers/pseuds/Emerald_Lazers
Summary: <blockquote class="userstuff">
              <p>I wanted a place to dump all my Undertale AU fanfictions. Different stories vary in characters and tone. </p>
<p>AU's used so far:<br/>Post-pacifist AU<br/>Core!Frisk, created by http://dokudoki.tumblr.com.<br/>Horrortale, created by http://horrortale.tumblr.com.</p>
<p>(More to be added in time.)</p>
            </blockquote>





	1. Post-Pacifist: A Cold Night

**Author's Note:**

> I will be doing more. For earlier updates on these one-shots, follow me on tumblr (http://emeraldlazers.tumblr.com/)

So this is what camping is like? Not being able to sleep because it’s too cold? It’s as if the air inside the tent was freezing Asriel’s eyelids open. He wondered how Frisk managed to sleep.

He rolled over in his star patterned sleeping bag to check on them. Not well. Not well at all. They were asleep but they were curled up in a ball, shivering. Asriel remembered his best friend didn’t have a coat of fur, so it would be even worse for them. The sight of them freezing was like a weight pushing down on Asriel’s chest.

He thought what he could do. Would that be weird? Would he be a bit too… clingy if he went through with his idea? Maybe Frisk would tease him about it later, but he had to do something.

He unzipped the sleeping bag as far as the zipper could. The temperature was dropping fast. Then he pulled it off and it was like a bucket of ice water was dumped on him and his thin pajamas.

Even more awake now, he scooted along the floor and unzipped Frisk’s sleeping bag. Just a little, he didn’t want them to be even more cold.

He slipped inside with Frisk; it was a tight squeeze. The idea was to use his body heat to help them not turn into a popsicle. Then he reached out, grabbed his sleeping bag and draped it over the two. He felt a bit awkward being so close while Frisk wasn’t even consious… but it was comfortable.

Frisk stopped shivering so he guessed it was for the better. This would be a bit weird to explain tomorrow. If he were to be honest, he himself still felt a bit uncomfortable. He never knew anyone that allowed him to get this close before. Well, Frisk was a sleep, so technically…

He felt movement in the cozy cocoon and then a hand grabbed his softly. He didn’t realize it until it was all gone that he was feeling tense. He gently pressed his head against Frisk’s. Why was he worried? Everything was fine. He slowly shut his eyes and drifted off to sleep.


	2. Core!Frisk AU: White Noise

**Summary for the Chapter:**

> Core!Frisk is created by http://dokudoki.tumblr.com/

**Notes for the Chapter:**

> I will be doing more. For earlier updates on these one-shots, follow me on tumblr (http://emeraldlazers.tumblr.com/)

It is a place that can only be described as… everywhere. The being that was once human looked around the solid white surroundings that stretched on forever. No one, other than Frisk themselves, could ever exist in this place.

Normal people, no matter how intelligent, can never even grasp the faintest Idea of what it was like to exist here. Sometimes it was too much, but there wasn’t exactly anything Frisk could do about it, other than listen. They heard voices all the time. In fact, a literal endless number. They could process every single one individually, whether it is poetry or white noise. Every detail, no matter how small, was fully comprehended by Frisk. There was no way to not to hear it.

They could see it too. The white surroundings only appeared white because all the colors of all the images added up to appear blinding… to most. Every infinitely small point in front of them represented a single point in space and time in a single universe among an endless number. Frisk’s whole field of view was consumed by these infinitesimal windows to other places.

They could even go to these places. Walking, talking, dancing, singing, or anything a normal person could do. Frisk could see their own ghostly projections doing whatever they wanted, wherever they wanted with whoever, or whatever.

Their form recreated in the image of their long deceased human body. That is the form they preferred, but they could always change it. As long as there was the slightest chance they wanted to look like something else, it happened. This was because of the one constant that rang true for even the strangest of places: math.

Frisk has been here forever, or perhaps for only an instant. The concept of time doesn’t exist here… or maybe there is nothing but time? It has given them the ability to think. They have thought of everything at this point, but it doesn’t hurt to pretend this is the first time.

What they wouldn’t give to talk to somebody normally. They can send projections of themselves into other universes to speak, but it’s not the same. They already know how the conversation will end, as well as every variation to it. They want it to be real. They want to talk to someone and not know how the other will respond.

And they didn’t want to be called their fake name. Of course, there were many versions of the same conversations where Frisk was called by their real name, but there were just as many where they are not. Part of them hated the abbreviations people spoke, referring to them as simply core. Merely a label to distinguish them from the many other Frisk’s. They don’t want that, they want the name they were born with. They wanted to just be a normal person. Frisk. Just Frisk.

There were also thoughts that fully embraced the abbreviated name. Math. Random chance. Entropy. Chaos theory. It’s like being a slave to numbers. Everything Frisk could possibly do will happen, because math dictates it will. When compared to the vast infinite that is Frisk’s existence, anything is possible. All possibilities have come to pass.

Frisk simultaneously snaps under the pressure of their own being and wipes out endless numbers of innocent life forms in every conceivable way. At the same time they remain completely levelheaded and are able to help an equal number of universes and timelines be saved from some terrible threat. Frisk has as many countless enemies as they do friends or even lovers. Every possible outcome…

However there is one exception; one truly unique outcome that can never happen any other way. There has, and will, only be one Frisk to endure the same fate. Frisk can see and experience all, therefore they are never alone; their infinite companions keeping them company. Yet, that too feels like white noise. There will only ever be one person in this place for all eternity.

Yet, random chance dictates that this feeling, too, shall pass. It already has.


	3. Horrortale AU: Now and Forever

**Summary for the Chapter:**

> Horrortale AU, created by: http://horrortale.tumblr.com/

**Notes for the Chapter:**

> I will be doing more. For earlier updates on these one-shots, follow me on tumblr (http://emeraldlazers.tumblr.com/)

Chara collapsed in the doorway to Asriel’s room. The red eyed monsters looked up in shock. Asriel would have rushed over to help if he was able, but Chara knew that was not the case.

Chara still wore the bulky, over-sized and now dented suit of armor. It was the smallest size they could steal from the castle’s armory. They didn’t know exactly how many of their bones were broken. It felt like all of them, but in actuality, It didn’t matter; Chara had found what they had searched for.

“Chara?” Asriel called meagerly, straining for his voice to be loud enough to hear. “W-what happened?” After a long pause, full of heavy breathing, Chara finally responded.

“I broke Asgore’s rule,” Chara said through huffs of air. “He didn’t like it.”

“Where did-”

“Wait,” Chara interrupted, “don’t talk, you need to save your strength.” The accursed sickness had been draining the small monster of his strength for far too long without any sign of stopping. Chara never stopped resenting themselves for getting too close while they were affected by the same ailment. They had survived, but Asriel was going to die because of them.

Chara, still wearing the bronze armor, pushed through the pain that wracked their whole body and slowly made their way over to Asriel’s bed and sat down next to him. Asriel looked at Chara with red, sad eyes. They cupped the side of Asriel’s furry, soft face and smiled as best as they could.

“Asgore didn’t like me sneaking out,” Chara under-stated, “luckily he got bored before he killed me.” Asriel opened his mouth to speak again, but Chara held up a hand. “I’ll be okay, and now, you’ll be okay too.” Chara grabbed a leather pouch from their belt and opened it, revealing a solid black crystal shard.

If the magical black flowers, the ones capable of curing all sickness, grew in the underground, this whole thing would be easy. However, it was not easy. The flowers were on the surface, behind the magical barrier that Chara, on many occasions, had tried and failed to force themselves through.

However, this black shard, a Serebus Crystal could help him… at a price. A price Chara had pondered again and again. A price they concluded they were willing to pay if it meant helping the only friend they ever had.

Some said that the Serebus Crystal is why monsters were banished underground and not anywhere else. Those who sought its’ terrible power would be ripped apart by hordes of savage monsters before ever finding one. But now Chara had it. 

“Remember when Asgore had one of his episodes and you stood in front of him to protect me?” Chara said, looking at the cracks in Asriel’s left eye. “This is me, paying you back.”

Chara held Asriel’s hand for a few long second before stepping away to the center of the room. Their somewhat functioning arm stripped off their breastplate. It clattered to the wooden floor. Chara took the Serebus Crystal and held it high in the air. Now they needed to recite the forbidden words. Chara took one last look at Asriel before returning to their dark task.

“Oridei,” Chara began, “klaatu barada nikto, nathrazem.” They crystal began to vibrate in Chara’s hand, resonating with the beat of their heart. “Faratus Itto baladash.” The incantation was cast.

They brought the crystal to eye level to examine it. The darkness inside its’ crystalline structure began to flow and move. It was like there was something trapped inside it, searching for release.

It was time to let it out. Chara held it out in front of their chest with both hands, the sharp end pointed straight at their heart. “Don’t worry,” Chara reassured, “I will take care of everything.” Before Asriel could protest, Chara plunged the shard into their chest and the world immediately vanished and was replaced only with darkness. 

They didn’t feel pain, even the sensation of their previous injuries faded. But it was cold, bone chillingly cold. This wasn’t a good Idea; it was a mistake, but a part of them knew it was too late. Their surroundings still resembled Chara and Asriel’s room, but were covered in twisting shadows, like the ones inside the crystal. Thankfully, Asriel was not here.

The crystal shard was still embedded in their chest, chilling them to their core. They were facing the bed, they had the overpowering urge to keep staring straight forward, to never turn around. Chara knew they were not alone. The ancient tomes and scriptures said it would be here. Asriel needed them, that was the only thing that kept them from trying to call off this whole thing.

They slowly began to turn around. Their very essence screamed to stop, to look away. Their heart was beating rapidly. They had to close their eyes to finish the entire turn towards the doorway. It felt like their eyes were trying to sink back into their head, away from what loomed in front of them.

Finally, after a deep breath, they opened their eyes. The completely solid black figure stood in the doorway. It had long stick-like arms and legs with a similar thin build. It had no face. It looked very simple, maybe not even scary compared to the other things in the underground, but Chara knew what they were dealing with. It felt like their blood had frozen in Chara’s veins.

They remembered tales about the others that had come here seeking the same figure. All of them sought petty things like fame and power. Those people had no Idea of the true consequences for seeking this being. It always resulted the same way. Those people were foolish and lost it all, before living out the rest of eternity in agony. Chara only wanted one thing from it. They were willing to give it all up for Asriel to live.

After a long, painful silence, Chara pulled together the smallest spark of courage they could muster, and spoke. “I… I come seeking power. Not for selfish reasons or personal gain, but to be able to save a single person. I am willing to give up everything in return for the ability to cure him of his sickness so that he may live.” It was exactly as they had rehearsed.

In response, the creature reached out a long, thin hand, black fingers outstretched. The action put the words ‘ _Are you willing to bare the consequences?_ ’ directly into Chara’s mind. Maybe this was their last chance to call it off; to yank the shard from their chest and bury it in a place that no one would find it.

“Yes,” Chara responded grimly, “now and forever.” An invisible force pulled at something. A small red wisp, the only color in this dark room, was pulled out of the shard in Chara’s chest.

The small, glowing object hovered in the air for Chara to see before it was pulled into the dark figure’s grip. It crushed it in its’ hand. The feeling of coldness, and even the looming dread faded. Along with so much else. They couldn’t say what was lost exactly, but they knew that it would never return. In this life or the next.

The figure re-opened its hand, the blackness of its’ form lifted up off its’ fingers in dark blobs. The floating shapes began to combine, forming a blackened replica of what had been taken from Chara. The figure held out its’ hand and the darkened wisp moved silently through the air and disappeared back through the crystal, and into Chara.

The words ‘ _It is done_ ’ circled through their head. The shadows that coated the room began to twist and fold, revealing patches of color. The creature in the shadows faded away, while the darkness continued to warp, folding in towards Chara, funneling onto a point on their back.

When the room had returned to the normality of before, Chara noticed something, some extra weight on their back. They turned their head and saw a pair of large shadowy wings sprout from some place between their shoulders. It rippled like fire, and it was heavy. So heavy; weighing down Chara’s very spirit, or at least what was left of it. They were so tired, but they knew they could never sleep. This was the price, or so they thought. 

The thing named Chara now stood in their room, staring at an open doorway. The black crystal shard sticking out of their chest was gone. All of their broken bones, cuts and bruises seemed to have vanished. Asriel, on the other hand, still needed to be healed. Now, for better or worse, Chara was now cursed with the power to do it. As Chara turned to look upon Asriel, they saw him staring back with a look of horror. He was shaking.

“It’s okay,” Chara said, their very words heavy, “I will make everything right.”

“I…I trust you…” Asriel responded quietly, straining to not sound afraid. Chara slowly walked over to him, and lifted him up in their arms with ease, even though he was as large as Chara. After everything, he still felt real. A huge sense of relief swept through them.

A part of them thought the ability to care about Asriel may have been taken, but thankfully, that did not come to pass. Chara stood for a few seconds, holding Asriel in their arms, knowing that their sacrifice would be worth it.  
Chara turned and started walking to the barrier. Asgore caught sight of them from the living room.

“Where are you going?” He growled. Asriel tensed in Chara’s grip. However they themselves didn’t even react. “It is forbidden to leave. I will reign you neck if you leave again!” Asgore screamed. The King was Already at the shouting phase, but Chara didn’t care.

“Back off,” was all Chara said in a monotone voice. They walked down the stairs, dead set on reaching the Barrier room. The space of the long hallway curved and distorted with a single flap of their shadowy wings. They reached the end in only a few seconds.

They stepped into a huge open room, their field of view was consumed by the sight of a massive curtain of red light; The Barrier. With Asriel being held gently in their arms, they walked forward. As dark stone floor faded into undefined red, Chara felt a presence.

Asgore stomped into the room. He lifted his trident over his head then threw it with one powerful motion. Chara folded their wings around both Asriel and themselves. The trident harmlessly bounced off.

“Do you take me for a fool?” shouted Asgore. “I will not be disrespected in my-” Chara turned, and with one index finger, an arc of black lightning shot forth, snaking through the air and striking Asgore in the chest. He collapsed to the ground immediately, movements random and sporadic. He was screaming. Chara could have killed him then and there, but Asriel spoke.

“Chara,” he said in a panicked, raspy voice, “Please don’t!” Chara stopped the stream of lightning without hesitation. Whatever he wanted is what they wanted. They didn’t even give Asgore a second thought.

Chara turned to look at the curtain of light ahead of them. The tips of their wings wrapped around Chara and Asriel, the ends converging on a single point. A spot of darkness appeared on the barrier, growing, like a cavity devouring a tooth. The patch of darkness was as large as the two now. Chara stepped through.

They walked up through a long dark corridor, another red light at the end. Not another barrier, but the sky. The two now stood at the entrance of a large cave. Chara looked out at the landscape. The sky was awash in a dim red from the perpetual blood moon of the night. Withered trees made up a forest. They needed to find the black flowers. They knew who had them, the humans of the nearby village.

The two traveled for some time, using a combination of using Chara’s shadowy wings as well as normal walking. Chara knew they were going in the right direction; they just did. Asriel said little. Both of them were content to merely be in each other’s presence. That, or maybe Asriel was simply too weak to speak. _Soon_. Soon everything will be right.

Then Chara saw it in the distance. A village, surrounded by the faint yellow-orange glow of torchlight. All they knew is that the flowers would be somewhere there. They would get them and heal Asriel, no matter the cost. Afterall, they had already paid enough.

“I need you to be strong Asriel,” said Chara. “I promise no harm will come to you.” Asriel’s only response was squeezing Chara’s shoulder lightly with their soft paw. Chara began to walk. 

~*~

“What do you mean you won’t tell me?” Chara roared to the knight in armor standing out from the crowd. Chara stood in the dimly lit village square. Small wooden buildings lined the gravel streets, a well sat in the middle of the square. More noticeably was the huge ring of people surrounding Chara. Most of them yelled absurdities, a few even tried to throw bricks and rocks. Chara already had a large cut on their forehead, above their left eye, and they were losing patience. Invading the homes of these villagers was Asriel, still being held in the grip of Chara; a monster in the clutches of a demon.

“I would never give it up to you!” the knight yelled back, his voice managing to peak the endless ocean of sounds. “You sold your soul to help that thing!” He knew. He knew where the flowers were. He knew how to save Asriel, and Chara wasn’t going to let this man stop that.

Chara pointed their finger, and the same magic that brought Asgore to his knees struck the knight. The crowd gasped as the man fell to his knees, clutching his chest. “Tell me!” Chara yelled again.

“Chara, stop, please!” Asriel said as loud as his weak, raspy voice would carry. Chara hesitated for a moment then stopped. _Anything_ for him. It was just that… Chara could feel Asriel slipping further and further away. The end for him was close.

“Where is it?” Chara yelled wildly once again to the crowd. The air had turned completely silent. By the Chara calmed down enough to sense it coming, something heavy slammed into the back of Chara’s head. They and Asriel fell to the ground. Chara’s vision was blurry, the back of their head moist and experiencing biting pain.

They quickly pulled themselves together. The knight was already on their feet and running toward Chara. They sprung up, but the knight had a metal gauntlet locked around Chara’s neck, his other arm raising a flintlock pistol. As the barrel of the gun took aim at Chara’s forehead, Chara’s hand shot up, their nails coated with layer of fiery blackness.

Chara’s nails dug into the exposed flesh beneath the knight’s helmet. The skin sizzled and bubbled visibly but the man kept the gun steady. The two of them remained locked in a standoff. If one killed the other, the slightest twitch would obliterate the first. If one backed down, the other would die.

“Help him.” Chara hissed.

“I would rather die than help a mongrel.” The knight snarled. Chara dug in their nails a bit further, the man winced ever so slightly. However, he didn’t show any sign of backing down.

“Fine,” Chara said, already knowing how this would end. “What do you want?”

“You’re head.” He said arrogantly. Yes, of course. There was one more thing that needed to be given to help Asriel. It didn’t look like they had any other option anyway.

“Fine,” Chara said. “My life in exchange for Asriel’s.” The knight tilted his head and seemed to consider the offer.

“If it means being rid of an vile creature like you, then so be it. Now stand back.” Chara didn’t move their hand immediately.

“Listen to me,” said Chara in a quiet, deadly serious voice. “If anything happens to the monster that lies on the ground, even the slightest scratch, just know that there will be no place you could hide from me. In this life or the next.” The knight slowly nodded his head in response.

Chara let their arm move away from his neck. They kneeled to the floor, wings closed in, head bowed. Asriel squirmed to reach them, but was too weak to move very far. Chara turned their head and gave him a gentle, genuine smile. “Goodbye, brother.” Chara whispered, “I love you.” The man lowered the barrel of the gun to the crown of Chara’s head and pulled the trigger.

The pain was excruciating but lasted only an instant. Yet… this was odd. Their dark wings had faded to nothing. Their body was crumpled on the floor, in a pool of their own blood. How could they know this? They were supposed to be in…  
They could see everything, at all angles, not just what was in front of their eyes. They saw their body below them, and also the sky above all the same. They were not dead, somehow. Chara tried to move their mysterious non-form, but could not. They tried to speak, but could not. All they could do was observe an entity that remained outside the realm of mortality.

Chara couldn’t hear anything, but they saw the man gesture to a few villagers. No doubt to fetch the flowers and heal Asriel. If Chara was trapped here for all eternity, it would be worth it, as long as Asriel was alive. A few minutes passed before Chara saw the villagers returning from some far off building. What Chara saw made all rational thought explode. They knew what it meant.

 _No. No, no, no, this can’t be happening!_ Chara thought. The villagers were not carrying black flowers; they were carrying a human sized wooden crucifix. They wouldn’t dare! Chara and the knight had a deal. Chara struggled to move, to use their power, to do anything but their mind was chained to a point above their body.

The villagers set the cross down besides Asriel. They picked up the small monster child and placed him, arms spread out, over the wooden frame. Chara still tried to thrash against their mental prison yet still nothing happened.

They watched a large metal nail be hammered through one of Asriel’s paws. Asriel tried to move now, but they were too weak, only being able to twitch slightly. His eyes were wide, his mouth agape. One by one, Chara watched their best friend and brother have his limbs nailed to a piece of wood. His blood trickled onto the ground.

‘ _How could you do this, you monsters?_ ’ Chara wanted to scream. They were literally unable to look away, they saw everything. The villagers lifted the cross, then turned it upside down so Asriel’s head dangled just above the ground. The man who had murdered Chara now casually walked over to Asriel, a sword in his hand. He looked almost happy.

Chara tried for one last attempt to break free of their bonds and intervene. Still nothing. The man put the blade of the sword under Asriel’s chin, and cut his throat.

 _NO!_ Chara screamed silently. They could do nothing except watch. Chara’s tidal wave of grief turned to boiling anger. They had the unrelenting desire to see this man suffer painfully and die. But, all they could do was watch.  
And like that, Chara, foolish Chara had succumb to the same fate of all those before them. There are never exceptions. They had made a deal with something evil only to result in losing everything. This man was no different than the black figure in the shadows. Both had come pray on Chara’s own ignorance, only to take it all away. Now and forever.


End file.
